Assessment of groundwater occurrence in a typical schist belt region in Osun State, Southwestern Nigeria using VES, aeromagnetic dataset, remotely sensed data, and MCDA approaches

摘要

Abstract This study presents modelling of groundwater potential in a typical schist belt region in Osun State, Southwestern Nigeria using electrical resistivity, aeromagnetic, remotely sensed data, and multi-criteria decision analysis (MCDA). Lineaments extracted from filtered and enhanced Landsat 8 OLI satellite imagery and aeromagnetic data were superimposed to generate lineament intersection, which was subjected to line density in the ArcGIS 10.5 environment to produce lineament intersection density. Eighty (80) vertical electrical soundings (VES) using Schlumberger configuration were acquired within the study location. The geoelectric parameters from the VES interpretation were used to determine the second-order parameters. Integration of electrical resistivity, aeromagnetic dataset, and remotely sensed data was subjected to multi-criteria decision analysis (MCDA) using analytical hierarchy process (AHP) to model the groundwater potential of the investigated area. Four distinct groundwater potential zones, very low, low, moderate and high zones, were identified. Boreholes and static water level data across the study area were used to validate the accuracy of the groundwater potential map. The prediction accuracy obtained showed that the techniques used in this study are capable of producing reliable and accurate results.